
CompAir DH
Oil-free single-stage compressors 15 to 37 kW – water-injected, single-stage, fixed speed and RS
There is not a drop of oil anywhere in the compressor: the DH series lubricates, cools and seals the compression with treated water. It is certified to ISO 8573-1 Class 0 and as silicone-free.
The single-stage, direct-drive compression element needs neither gearbox nor V-belt. With speed control, it matches the delivery precisely to demand.
Motor power
15 to 37 kW
Pressure
5 to 10 bar
Flow rate
0.32 to 6.87 m³/min
Air purity
Class 0
Why the DH series?
The injected water cools so effectively that compression stays below 60 °C, almost isothermally. An aftercooler in the compressor is unnecessary, which saves energy and avoids pressure loss.
Low speeds and balanced forces in the compression stage protect the bearings. They are permanently sealed and need no oil. The injection water is treated by reverse osmosis.
- Completely oil-free, certified Class 0 and silicone-free
- Single-stage, direct drive, no gearbox
- Compression below 60 °C, no aftercooler required
- Permanently sealed bearings without oil lubrication
- Available with variable speed drive
- Closed, sound-insulated enclosure
Delcos XL controller
The high-resolution touchscreen shows the pressures and temperatures of both stages, water level and temperature, flow rates and operating hours. An SD card stores the values for analysis.
- Touchscreen with clear menus
- Pressure and temperature at all measuring points
- Average flow rate per week
- Motor speed on RS models
- Base load sequencing as an option
Product images




Technical data
Fixed speed – air- and water-cooled
| Compressor model | Cooling method | Motor power | Operating pressure | Flow rate | Dimensions L × W × H | Sound pressure level | Weight | ||
|---|---|---|---|---|---|---|---|---|---|
| [kW] | [bar g] | [bar g] | [m³/min] 8 bar g* | [m³/min] 10 bar g* | [mm] | [dB(A)]** | [kg] | ||
| D15H | Air | 15 | 8 | 10 | 2,30 | 1,80 | 1309 × 848 × 1612 | 68 | 672 |
| Water | 15 | 8 | 10 | 2,30 | 1,80 | 1309 × 848 × 1612 | 65 | 624 | |
| D22H | Air | 22 | 8 | 10 | 3,50 | 2,89 | 1309 × 848 × 1612 | 68 | 691 |
| Water | 22 | 8 | 10 | 3,50 | 2,89 | 1309 × 848 × 1612 | 65 | 643 | |
| D37H | Air | 37 | 8 | 10 | 5,86 | 5,04 | 1686 × 886 × 1657 | 71 | 960 |
| Water | 37 | 8 | 10 | 5,86 | 5,04 | 1686 × 886 × 1657 | 61 | 860 | |
Variable speed – air- and water-cooled
| Compressor model | Cooling method | Motor power | Operating pressure [bar g] | Flow rate [m³/min] | Dimensions L × W × H | Sound pressure level at 70% load | Weight | ||
|---|---|---|---|---|---|---|---|---|---|
| [kW] | min. | max. | min.* | max.* | [mm] | [dB(A)]** | [kg] | ||
| D15H RS | Air | 15 | 5 | 10 | 0,32 | 2,34 | 1309 × 848 × 1612 | 67 | 687 |
| Water | 15 | 5 | 10 | 0,32 | 2,34 | 1309 × 848 × 1612 | 64 | 639 | |
| D22H RS | Air | 22 | 5 | 10 | 0,68 | 3,45 | 1309 × 848 × 1612 | 67 | 687 |
| Water | 22 | 5 | 10 | 0,68 | 3,45 | 1309 × 848 × 1612 | 64 | 658 | |
* Data measured and stated in accordance with ISO 1217, Edition 4, Annex C & Annex E, within the following tolerances: inlet pressure 1 bar a; inlet temperature 20 °C; relative humidity 0% (dry)
** Free-field sound measurement in accordance with ISO 2151, tolerance ± 3 dB(A)
Data from CompAir. Flow rate to ISO 1217, Annex C or E. We will be happy to determine with you which version and pressure are right for your system.
Frequently asked questions
What does oil-free to ISO 8573-1 Class 0 mean?
Class 0 is the strictest purity class for oil in compressed air. A compressor certified to it puts no oil into the air, neither as droplets nor as vapour. You therefore need no oil filters and no oil-water separator for the condensate, and the risk of contaminated products disappears.
How is the injection water treated?
A reverse osmosis unit inside the compressor treats the water. A permeate pump keeps water consumption low.
Fixed speed or variable speed (RS)?
A fixed-speed compressor is most economical when it runs at a steady load. If your compressed air demand fluctuates during the day, a variable speed RS compressor continuously adjusts its delivery and saves electricity. On request, we measure your demand with a compressed air analysis and tell you what is worthwhile.
Who maintains the compressor?
We do. As the CompAir partner for north-western Switzerland, we maintain and repair your system with genuine spare parts and service kits. If your compressed air supply fails, you can reach our on-call service on 062 552 00 88.
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Which compressor is right for your business?
Compressed air demand, pressure, operating times and available space determine the choice. We advise you, supply the compressor with air treatment, install the system and take care of service.